1 Department of Radiology, Key Laboratory of Birth Defects and Related Diseases of Women and Children of Ministry of Education, West China Second University Hospital, Sichuan University, 20# South Renmin Road, Chengdu, Sichuan 610041, China.
2 Department of Pathology, West China School of Medicine, Sichuan University, 37# Guo Xue Xiang, Chengdu, Sichuan 610041, China.